Rotary atomizer

Abstract

A rotary atomizer for atomizing a coating material for the coating of workpieces having a housing, a turbine wheel which is arranged in the housing and can be driven in two directions of rotation, a bell cup can be set in rotation by the turbine wheel about an axis of rotation and also a device for determining a rotational speed, wherein the device comprises an optical waveguide and a disc, which is indirectly or directly connected to the bell cup or the turbine wheel for rotation therewith and has an optically detectable structure, wherein the optical waveguide is designed for recording the optically detectable structure and for passing on the recorded structure as an optical signal in the housing. The optical waveguide has a first information channel and a second information channel, which are respectively designed for passing on an optical signal independently of one another.

What is claimed is: 
     
         1 . A rotary atomizer for atomizing a coating material for coating workpieces, comprising:
 a turbine wheel, which is drivable in two rotational directions,   a bell cup which can be set into rotation about an axis of rotation by the turbine wheel, and   a device for ascertaining rotation-related items of information, wherein the device comprises a rotating body and an optical waveguide, wherein the rotating body is directly or indirectly connected in a rotationally fixed manner to the bell cup or the turbine wheel and has an optically detectable structure, wherein   the optical waveguide is designed to acquire the optically detectable structure and to relay the acquired structure as an optical signal, and further wherein   the optical waveguide has a first information channel and a second information channel, which are each designed to relay an optical signal independently of one another.   
     
     
         2 . The rotary atomizer as claimed in  claim 1 , wherein the optical waveguide has two optical waveguide fibers for relaying optical signals from the first information channel and the second information channel. 
     
     
         3 . The rotary atomizer as claimed in  claim 1 , wherein
 the optically detectable structure forms a brightness contrast on the rotating body,   a first optically detectable structure is arranged on a first circular line of the rotating body and a second optically detectable structure is arranged on a second circular line of the rotating body, wherein   the first optically detectable structure on the first circular line generates a first optical signal having a first pulse frequency and on the second circular line generates a second optical signal having a second pulse frequency, wherein the first pulse frequency is greater than the second pulse frequency.   
     
     
         4 . The rotary atomizer as claimed in  claim 3 , wherein the first pulse frequency is at least twice as large as the second pulse frequency. 
     
     
         5 . The rotary atomizer as claimed in  claim 3 , wherein the first optical signal enables a rotational direction recognition and/or an acceleration recognition. 
     
     
         6 . The rotary atomizer as claimed in  claim 3 , wherein wherein the first optical signal is transmittable via the first information channel and the second optical signal is transmittable via the second information channel. 
     
     
         7 . The rotary atomizer as claimed in  claim 1 , wherein the first information channel and the second information channel are differentiable by the polarization thereof. 
     
     
         8 . A method for coating objects by means of a rotary atomizer as claimed in  claim 1 . 
     
     
         9 . A facility for coating objects such as vehicle bodies by means of a rotary atomizer as claimed in  claim 1 .